Trouble updating iTunes 11.1.4
I tried updating my iTunes on my MacBook Pro to 11.1.4, and now I can't open iTunes at all. I checked Installed Software under System Preferences, and it reads as though iTunes was properly installed — but when I click on iTunes, nothing happens. I don't know what to do, and I don't want to lose all my music!
MacBook Pro, Mac OS X (10.6.1)